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Discussion Starter #101
It is the camera angle, in reality it is not as close as it appears, but as long as there is a gap it would be ok anyway..... i'll bow to Audi's superior knowledge on this one!
 

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Amazing to the people who design these engines, so much detail. I'm speechless at what's going on here, amazing work. The result is going to be epic.
 

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I have to agree that Audi makes some interesting engines.

Check out the later Audi V8's. The generation after this one had 5 valve per cylinder (40 total!). The generation after that was shorter. It is 18.3 inches long (compared to 20.6" for the one Paul is working on), and had chain driven cams. The chains are at the BACK of the engine. Its also wiiiiiider than the ABZ.

I am very interested in the W8 and W12 that VW designs and builds. They use VR heads. THe VR head is a very innovative valvetrain.

What I can't figure out is why the Germans (with thier super clever engineers), still have lower durability/longevity compared to the Japanese (Toyota's current QA issues non-withstanding).
 

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Discussion Starter #105
Another first for Mk1's here, i am running very big wheels on this car (for obvious reasons) and as a result some power steering would be a very nice option to have. I retro fitted a Mk1 years ago with a Mk2 system with all of its rack, pump, control systems etc etc, which worked but was all pretty heavy and i couldn't fine tune it. So this time around i have gone for a completely different approach.

Quite a few modern cars these days use an electric motor on the column to give a variable amount of power steering so i bought a Vauxhall Corsa column with this sort of setup and then proceeded to make a hybrid Mr2/Corsa steering column.

The lower half of this column is Corsa, the top half is Mr2, this means i can retain ALL of the Mr2 switchgear, my ignition barrel, the cowling, and even the adjustable rake will all work as before.





The icing on the cake with this mod is that there is an adjustable regulator box that plugs into the Corsa PS ECU, this is then mounted on the dash and i can control wether the system is completely turned off (will just feel like a normal Mr2 steering) or any amount of assistance can be dialled in right up to full assistance.

Now before anyone gets excited about the prospect of having power steering on their Mk1 i must stress i have other mods to do to the tube framing around the steering column on my mk1 so that this assembly will fit, so it is never going to be a kit i can offer unless your car is brought to me for surgery.

So i now have the worlds only PS equipped Mk1.... not that the V8 made it unique!
 

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Gordon Murray has stated that the NSX electric PS unit is "quite light". If GM says it's light, then that's really saying something.

Any other cars you know of (that we can get in the USA) have an electric PS column?
 

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Discussion Starter #108
Yes the Vauxhall (Opel there?) PS ECU runs the motor, and expects speed and tacho inputs, but the Toyota signals are incompatable at the moment, so there is a "mod box" on Ebay that allows you to control the amount of assistance from OFF to FULL via the PS ECU.

So at the moment it is not speed dependant variable, but i can set the amount of assistance to whatever level i want so will probably just find a happy level at all speeds and stick with that, and turn it to full for parking etc.

There are four wires to connect, main live, main earth, and power/earth for the mod box.
 

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MOre info on the Honda unit (NSX unit):
http://www.nsxprime.com/FAQ/Technical/eps.htm



When you get to that part, will you provide details on how you wire it so that it provides a fixed level of assistance?

Eventually, I hope to use an electric assist column possibly in my 93T (with electro-hydraulic -- to save weight), or in a kit or scratch built car I hope to build some day.

I ask because I don't understand how these units work. Do they automatically know which way to run the motor as you steer (because we are constantly switching from left to right) and the column knows this or does the outside computer determine this?
 

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Discussion Starter #110
Yes the whole unit is a self contained assembly that does everything, so it knows what direction you are turning (sensor on column) and assists in that direction based on speed and rpm (when in the factory corsa).

If i put a little time into it i could easily get the Toyota speed and rpm signals to work on this PS ECU to make it vary the assistance with speed, but i like having control of it with a knob on the dash.

I will of course show how it is wired up, but all it needs is four wires, two power feeds and two grounds, it's very simple.
 

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Paul, that crank trigger mount looks familiar :)

The Corsa EPS ECU needs the following inputs to function :-

1) RPM 12V (to prevent operation without the alternator running and hence flattening the battery)

2) 12V control signal which is effectively just on when the car is running (this comes from the body control module on the Corsa)

3) 50A fused 12V power.

This will get the column operating, however it will be generating maximum assistance constantly which will probably be a bit light at speed.

The VSS (Vehicle Speed Signal) is what varies the amount of assistance and can use a simple signal from an electronic speedo sensor. The RPM and VSS signals are what the eBay "mod box" generates.

I have got mine running in my Esprit without the "mod box" and giving variable assistance from the dash speedo ssensor and the tacho signal from the VEMS ECU, works a treat :)

Hilly
 

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Discussion Starter #112
Hi Andy, do you reckon the Toyota speed signal may well do the job then? I fancy having a switch on the dash that gives me control through the "mod box" or full auto variable. I didn't realise you had used this column on the Lotus! Great minds and all that :)

Yes i gave my engineer pics of your trigger adapter for reference, it was the best solution by far, please don't sue my ass :)
 
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